STEPWISE PHASE MODULATION OF ATOMS COUPLED TO A QUASI-CONTINUUM OF STATES IN A CAVITY

We study the interaction of a small number of resonant two-level atoms in a cavity coupled to a quasi-continuum of cavity modes. During the interaction we induce externally a phase step to one of the atoms. As a result an enhancement in the photon emission to the field is observe d. The phase step is obtained by a pulse which causes the atom to be o ff-resonance for a short lime interval. The effect is strongest in cas es where the number of atoms is small. The enhancement is not restrict ed to a small parameter range but should be observable in many systems even though the pi phase shift gives the best enhancement.